Plans Sidney

Do I need a visa to go to Australia from Brazil? ?
I am planning to go to Sidney(from Brazil) in July of 2009. Probably from July 5th to July 12th(a week). Is there cheap hotels in Sidney, like B&B. I am going to a conference held in Sidney next year, so I would appreciate any information!
Thank you,
Gus!
OBS: I am brazilian, so do I need a visa from Brazil?
Just to clarify it is spelt Sydney. You will need a visa for this, you would only need a tourist visa which is quite inexpensive. The travel agent can help you with this or see http://www.immi.gov.au
I like the Accor chain of hotels, they have all levels, my picks are Novotel and Mercure, you can get a room for around $150. Ibis have cheaper options. http:///www.accor.com.au
Simple Plan Sydney Australia Zoo
Classic Books Library